Gutted mate, ask to see a copy of there calibration certificate for the speedgun used on the day you allegedly got caught! 9 times out of 10 they haven't got one.
I got caught a couple of years ago in the local village at about 8pm on a saterday night in the summer, supposedly doing 40 in a 30, got pulled over, when I ask him if I could see his calibration certificate for the gun he got all aggressive luckily his pso (police support officer) calmed him down, he gave me the ticket and off I went!
When I got the letter through I went against it saying I wasn't speeding, took about 6 months to go through then finally a letter saying I had to go to court!
Arrived at court with my lawyer ready to fight my case, the officer turned up to! When asked to go in to plead my case I was interrupted by the judge saying that the pso had not turned up to court as it was her day off, the paperwork had been lost due to having to go through so many offices, and the calibration certificate didn't exist because the speedgun he was using was not recognised by any of there handbooks!
So I was offered £400 compensation and walked out a happy man. Got a nasty look from the officer though.
Might be worth fighting it! There not always right!
Or you could just take the course!